Petra Stock
Japanese archaeologists crafted replica stone tools and put them to use in activities ranging from tree-felling to bone-scraping to assist in analysing artifacts.
The study, published in the Journal of Archaeological Science, is an example of practical archaeology – where researchers learn about the past by recreating it in the present.
First, researchers made 75 hand-held stone axes and adzes using a stone hammer and anvil and grindstones.
In line with real artefacts, the stone reproductions were made with an average length of 9.7cm, width of 5.7cm, and thickness of 2cm.
The tools were made from minerals called semi-nephrite (collected from the Matsukawa and Oumigawa Rivers in Japan), hornfels (from the Abo River on Yakushima Island) and tuff (from the Fujikawa River).
The replicas were then bound onto 3 different types of wooden handle – for an adze, axe and chisel – using thin strips of wood, lashed with fibrous grass.
Next, the researchers put the tools to use in 15 different activities to observe and categorise the macro fractures and microwear.
53 of the replicas were used for 10 ‘use’ activities, including tree-felling, wood-axing, wood-adzing, wood-scraping, antler-adzing, antler-scraping, bone-adzing, bone-scraping, hide-scraping, and carcass disarticulation.
Of those, 26 tools were used until fractured or blunted, and the remaining 27 stopped and observed at 500, 1000, 3000 and 5000 strokes.
They also investigated wear and tear from 5 non-use activities, such as accidental fractures that occur during production or re-sharpening and damage from trampling or transporting them in a bag with other tools.
Finally, 4 stone axes were retained unused as control samples.
From their experiments, the researchers then classified 9 types of macroscopic fractures from different tool uses. While different microscopic features were linked to specific worked materials.
The combination of macroscopic and microscopic traces can aid in analysing real artifacts.
For example, “A combination of percussive fractures and wood micropolish can serve as diagnostic traces to identify archaeological edge-ground stone tools that have been used for tree and wood percussion.”
The findings, can help in analysing the likely use of stone artefacts, such as found in Australia and Japan which date to 60,000 – 30,000 years ago, and may help identify when timber use began for early humans.
